Form clamp



May 6, 1969 J. a PREBUCH 3,442,4 2

FORM CLAMP Filed Dec. 5, 1965 INVENTOR.

JOSEPH G. PREBLICH ATTORNEYS United States Patent 3,442,482 FORM CLAMPJoseph G. Preblich, Santa Rosa, Calif., assignor to Olsen ConstructionCo., Santa Rosa, Calif. Filed Dec. 3, 1965, Ser. No. 511,550 Int. Cl.E04g 17/02; B28b 7/26 US. Cl. 249219 2 Claims ABSTRACT OF THE DISCLOSUREThis invention relates to a clamp and more particularly to a clamp whichmay be used to support two members, such as the walers of a concreteform structure, at right angles to each other.

Although my invention may be used in a number of applications where itis desirable to secure two adjacent members at right angles to eachother, I have found it to be of particular interest in concrete formconstruction. In constructing forms for the pouring of concrete, boardsor plywood panels are held in place by external reinforcing supportsknown as walers. These members are usually standard 2 x 4s or otherconvenient stock timber selected to have sufficient stiffness to supportand reinforce the boards or plywood panels against the pressure of thewet concrete being held in place prior to the initial hardening orcuring period.

A problem that frequently occurs in the above-described formconstruction utilizing walers and the like is the placement and supportof two forming surfaces having edges which abut against each other toform a corner. In FIGS 1A and 1B of the drawing accompanying thisspecification, I show two typical prior art solutions to this problem.In the sectional plan or elevational view of FIG. 1A, poured concreteindicated generally at B is held in place by form boards 12 and 13 whichin turn are backed up and supported by walers 14 and 16. These membersare in turn held in place by so-called kickers 17 and 18 which may besecured by nailing or other suitable fasteners to walers 16 and 14,respectively. Thus kicker 17, which, for example, may be a 2 x 2 timber,restrains waler 14 and form board 12 from move-ment away from the zoneof concrete pouring, and kicker 18 restrains waler 16 and board 13 fromsimilar movement. This type of form construction, however, has severaldisadvantages; for example, it is relatively difiicult to obtain goodalignment of the walers supported form boards since it is necessary tonail or bolt some of the kickers while holding the adjacent walers infinal assembly position. This method also requires extra material forkickers, two for each corner, which are usually provided along eachwaler intersection; and the walers themselves must extend out beyond thecorner of the intersection of the concrete forms to provide stock fornailing or bolting up the kickers. Also, particularly when nailing isused, the walers are often split and cannot be reused after ripping downthe forms. Another disadvantage is that labor costs are relatively highfor this type of form construction because of the necessaryinterconnection of kickers and walers which may occur as often as everytwo feet throughout the entire length of a given form corner.

Another prior art solution with which I am familiar is shown in thesectional view of FIG. 1B where walers 24 and 26 reinforce forms 22 and23 to constrain the concrete indicated generally at C. Here the walersare held in place by heavy flexible wire 27. The wire is wrapped aroundand passed between the walers through holes 28 formed in form boards 22and 23. The heavy wire may be twisted or drawn together in some othermanner either within the concrete zone as indicated at D or outsideadjacent to one of the walers. One of the disadvantages of this methodis that the holed in forms 22 and 23 ordinarily require caulking priorto the pouring of concrete to avoid protrusions of concrete along thefinished wall. Where extensive corner forming is required, suchcaulking, and the necessity of cutting and trimming member 27 after thepouring and stripping of the form, increases costs substantially.

It is a primary object of the present invention to provide a pair ofbearing plates to bear flatly against the outer two surfaces of a pairof workpieces which are disposed to one another at a predeterminedangle. A back plate is secured to each of the bearing plates at an anglewhich will align the back plates so that they are substantially parallelto each other when the bearing plates are positioned for hearing contactagainst the outer two surfaces of the workpieces. Compression means isprovided with the device for urging each of the back plates andconsequently each of the bearing plates toward each other so that thebearing plates are tensioned against the outer surfaces of theworkpieces and held in clamped relationship.

It is another primary object of the present invention to provide acorner clamp for holding a pair of workpieces which workpieces are sopositioned relative to one another so as to define the apex of apredetermined angle. Such a corner clamp comprises a pair of plateshaving bearing surfaces for engaging the workpieces therebetween. Afirst leg is secured to one of said plates and a second leg is securedto the other of said plates so that the legs and plates form a pair ofangles the sum of which is substantially equal to the predeterminedangle of the workpieces. The device also includes compression meanswhich is operatively connected to the legs for moving the legs into andout of bearing contact with the workpieces. The compression meanscomprises a she bolt inserted through each of the legs together with abearing nut threadedly secured to one end of the she bolt and stop meanssecured to the other end of the shebolt.

It is another object of this invention to provide a reusable cornerclamp to secure and hold members such as walers and concrete forms atright angles to each other while eliminating the need of additionalstructural members and associated construction operations.

A feature and an advantage of this invention is that the clampsthemselves are reusable. Also, the need for kickers is eliminatedaltogether while the forming materials, such as walers, are minimized;left undamaged by the clamps; and hence are also reusable on futurejobs.

It is another object of this invention to provide a corner clampcomprising a pair of clamping plates slidably mounted along an elongaterod. The plates are oriented so that their faces are at right angles toeach other, and the rod is provided with a stop at one end and anadjustable cathead or bearing bolt at the other end. The plates may beplaced in position bearing along the outside faces of a pair of adjacentwalers at right angles to each other and then drawn together by means ofthe bearing bolt so that the walers are securely supported by the facesof each of the clamps at right angles to each other. During tighteningof the clamping plates, the clamp itself may be supported in position bymeans of the elongate rod resting on adjacent walers.

A feature and an advantage of this invention is that any number ofcorner walers may be secured in fixed relative position to each otherwithout the use of additional structural members such as kickers or thelike which not only require additional material but relatively extensivelabor of installation and adjustment as well.

It is another feature and advantage of my invention to provide a cornerclamp for concrete forms which eliminates the need for drilling holes inthe form boards to accommodate clamping members of the twisted wirevariety and the need for caulking such holes or trimming the concreteprotrusions, and cutting the wires extending from the finished wall,which remain after pouring and stripping away of the forms.

Another object of my invention is to provide a corner clamp having apair of clamping plates with L- or angleshaped brackets having legssecured to one side of each of the plates. An opening is formed in theface of each of the plates which is in alignment with a similar suchopening in one of the legs of the L-shaped bracket. An elongate rod orshe bolt is provided which may be positioned through the holes in theclamp plates and brackets. One end of the rod is provided with a flangeand the other end with an adjustable bearing bolt or cathead. Theclamping plates may be aligned at predetermined angles to each other andpositioned to contact the backsides of a pair of walers set up tosupport form boards abutting each other at an angle equal to the sum ofthe predetermined angles. The adjustable bearing nut at the one end ofthe rod may be turned to vary and fix the maximum interval between theclamping plates and their attached brackets; in this way the walers maybe secured and clamped in fixed operating position.

A feature and an advantage of my invention is that the clamp may be usedto hold the corners of angleabutting form boards which do not requirethe use of walers. In such case it is merely necessary to provide fillerblocks under the clamp faces to provide clearance of the elongate rodsat the outside edge of the form corner. The clamps may then be appliedalong the entire length of the form corner as required.

Turning now to the drawings, FIGS. 1A and 1B are sectional views showingconcrete forms held in place at a right angle corner by certain priorart structures as explained above;

FIG. 2 is a sectional view of a concrete corner forming assemblyembodying my invention;

FIG. 3 is a side elevation taken along line 3-3 of FIG. 2; and

FIG. 4sh0ws a portion of my invention in side elevation with certaindetails clarified.

My invention is best understood by referring to FIG. 2 and the clampindicated generally at D. Although my novel clamp may have a variety ofapplications, I show it as applied to walers at the corner of a concreteform bounding the concrete zone indicated at E.

Forms 32 and 33, which may be made of boards in endto-end relationshipor abutting plywood panels, are held in place before the pouring of theconcrete. The form boards or plywood paneling are backed up andreinforced in place by walers 34 and 36 which may be fabricated ofstandard 2x4 timbers or other suitably sized members made of wood orother material. Such walers are generally required at relativelyfrequent intervals along the entire length of the forming structure,including the corner shown at F, to back up and reinforce forms 32 and33 against the high fluid pressures exerted by the fresh concrete whenpoured in the zone at E.

To firmly hold and clamp members such as walers 34 and 36 in place, mynovel clamping device provides a pair of clamping plates 37 and 38positioned to bear on the backsides of pairs of such adjacent cornerwalers. The

plates may be drawn together along rod 47 by means of bearing nut orcathead 52 which can be threadedly ad vanced along the rod in bearingcontact with back plate 39b secured to plate 37. Plate 38 is restrainedby means of flange washer 49 under cap screw 48. While clamp plates 37and 38 are loose, the entire clamp assembly may be supported in positionby resting elongate rod 47 on the end surfaces of walers 34 and 36. Insome cases it may be desirable to use pairs of walers to reinforce theform boards, in which case the clamp rod may be nested between thewalers thus imparting additional stability to my novel clampingarrangement.

L-shaped brackets or angle members indicated at 39 and 41, having legmembers 39a and 39b, and members 41a and 41b, respectively, are providedwith the ends of the leg members welded or otherwise suitably secured tothe backs of the plates indicated at 37 and 38, respectively. Legs 41aand 41b, and the portion of plate 38 between the legs 39a and 39b, andthe portion of plate 37 between the latter legs, are arranged here toform an isosceles right triangle. The hypotenuse of each triangle isthat portion of the clamping plate between equal legs 41a and 41b, and39a and 39b. An elongate opening 42 is formed in the face of plate 37and a similar such opening 43 is formed in the face of plate 38. A moreor less circular opening 44 is formed in leg 39b of the bracketindicated at 39, and a similar opening 46 is formed in back plate 41b ofthe bracket indicated at 41. The alignment of openings 42 and 44 isparallel to leg 39a, while that of openings 43 and 46 is parallel to leg41a.

An elongate rod or she bolt 47, which is shaped to fit through theopenings 44, 42, 43 and 46, is positioned through these holes with theoutside faces of plates 37 and 38 positioned to contact the backs ofwalers 34 and 36, respectively. A fiat washer 49 is provided under capscrew 48 which is threadedly engaged in a longitudinal hole at one endof she bolt 47. The flat washer prevents passage of thecap screw headthrough opening 46. Coarse square threads 51 are provided at the otherend of bolt 47 and threadedly engage the internal threads of cathead 52having wrench flats 53 and flared bearing portion 54.

With the alignment of holes 44 and 42 parallel to leg 39a of L-shapedbracket 39, and that of holes 43 and 46 parallel to leg 41a of bracket41, the face of clamping plate 37 may be aligned at right angles ornormal to the plane of the face of plate 38. By this arrangement, bothplates are maintained normal to each other as the plates are drawntogether during clamping by turning cathead 52, by suitable means suchas a wrench engaged against wrench flats 53. As the interval between theplates is varied to fix the maximum interval therebetween, the clampfaces in contact against the backs of the walers force the walers closetogether thereby forming a tight connection along the intersectionindicated at F.

The above described arrangement embodying my novel invention may berepeated throughout the concrete form construction wherever corners mustbe set up with forms to restrain the flow of wet concrete prior tosetting-up and initial curing. Thus it is understood that my inventionmay be employed along the waler reinforced intersection of form boardsat any angle in respect to the horizontal, i.e., vertical, horizontal,or at angles in between.

After the concrete has set-up, and the forms are to be stripped, it is arelatively simple matter to loosen my novel clamps and free the walersand form boards. Substantial savings are thus realized using myinvention, since the need for prying apart nailed walers, or unboltingthe several connections of bolted members, is avoided. In addition, nowalers are lost due to splitting during the stripping operation, or thevirtual destruction of a waler end once a hole has been drilledtherethrough to receive a bolt. Additional material in the way ofkickers is eliminated; and, in contrast to wire tying of the walersthrough the concrete zone, explained earlier, my invention avoids costlycaulking and trimming operations necessitated by such techniques.Moreover, the novel clamps of my invention, which eliminate therelatively costly and laborconsuming techniques just described, are inno way damaged by use and may be reused repeatedly in job after job,thus achieving even further convenience and economy of operation.

It is also understood that my novel clamp arrangement may be applied toangle-abutting form boards which do not require the use of reinforcingwalers. In such case it is merely necessary to plate spacer blocksbetween the clamping faces and the form boards to provide clearance andlocate the she bolt beyond the corner of the form structure.

I have described my invention in the foregoing specification in somedetail, but this is understood to be for the purpose of clarity ofexplanation and is not intended to impose unnecessary limitation. Forexample, I have described my novel clamping arrangement as applied toright angle corners for the sake of convenience. By changing the lengthof the legs of the brackets indicated at 39 and 41, other angularrelationships may be accomplished between the faces of clamping plates37 and 38, e.g., almost any angle from a very acute angle to an obtuseangle may be formed between the clamp plates and hence the concrete formboards. In general my novel clamp may be used to hold workpieces such aswalers 34 and 36 shown in FIG. 2 at any desired predetermined angletherebetween so long as the leg secured to one clamp plate, for exampleleg 39b secured to plate 37, is arranged parallel to the leg on theother clamp plate, in this case leg 41b secured to plate 38. Thisconstruction is also characterized by the sum of the angles between thelegs and the respective plates to which they are secured, for examplethe sum of angles 62 and 63, being substantially equal to the anglebetween the workpieces, i.e., angle 64 in the case of walers 34 and 36.

In the event that the angle between workpieces is selected to be greaterthan 90, i.e., an obtuse angle, it may be necessary to provide somemeans to assist the face of the plates to dig in and grip the backs ofthe walers. This may be accomplished by barbs or sharp protrusions 56 onface 138 of a typical clamp as shown in FIG. 4. Sharp protrusions 56that project outwardly from the face of the plate preferably are alignedat an angle generally inclined in the direction of the clamping motionof the plates when in operation. Such barbs or protrusions may also beuseful even for right angle or acute angle concrete form cornerconstruction.

Many other mechanical variations may occur to one skilled in the artupon a reading of this specification which are within the spirit of myinvention and scope of the appended claims.

What is claimed is:

1. In combination with a pair of abutting workpieces disposed at anangle to each other that are suitable for being held in direct contactwith wet concrete during the initial hardening period for said concrete,a corner clamp arranged to temporarily rigidly align said workpieces,comprising in combination: a pair of clamping plates, each including aface adapted to bear flatly against a respective outer surface of saidpair of abutting workpieces, said faces including a plurality ofprotrusions projecting outwardly therefrom for penetration intorespective of said workpieces; a pair of L-shaped backing plates securedat their outer ends to respective of said clamping plates, said backingplates each having a pair of interconnected legs, a leg of one of saidbacking plates adapted to be substantially parallel to a leg of theother of said backing plates when the clamping plates are positioned tobear against the outer surfaces of said workpieces; compression meansincluding an elongate rod spaced from said workpieces and adapted to bealigned within and extend from openings formed in said parallel legs andsaid clamping plates, said openings having centers in alignment witheach other and normal to the faces of said parallel legs when saidclamping plates are positioned for hearing contact against the outersurfaces of said workpieces, said rod being threaded at both ends, and apair of threaded members adapted for independent mating engagement withrespective ends of said rod, said threaded members having a bearing facefor contacting the outer face of respective of said parallel legs, saidpair of threaded members being separately adjustable so that the forcesbeing applied to both of said workpieces by said clamping plates can besubstantially equalized to retain said workpieces at said angle to eachother.

2. A corner clamp in accordance with claim 1 wherein one end of said rodis internally threaded while the other end of said rod is externallythreaded.

References Cited UNITED STATES PATENTS 1,538,496 5/1925 Wells 249194 XR1,564,924 12/1925 Alwyn 249-48 2,3 89,397 11/ 1945 Zimmerman 249-48 XR2,572,366 10/1951 McGough 249219 XR FOREIGN PATENTS 916,353 8/1954Germany.

WILLIAM J. STEPHENSON, Primary Examiner.

US. Cl. X.R. 25-431; 249194

